Ultrastructural and Chemical Characterization of a Cyanobacterial S-Layer Involved in Fine-Grain Mineral Formation

Abstract

Cyanobacteria belonging to the Synechococcus group are unicellular, marine or freshwater organisms which gain energy from light through oxygenic photosynthesis and carbon from CO2 (as HCO3- in the alkaline waters they usually inhabit). During CO2 fixation, HCO3- is taken into the cell and OH- is released, leading to alkalization of the microenvironment surrounding each cell (Miller and Colman, 1980). This pH effect has important geochemical implications in the natural environment.